The present invention pertains to the field of conveyor belts used for material handling. More specifically, the present invention pertains to a heated scraper blade and controls therefor for removing residual material from a conveyor belt.
In the use of conveyor belts for transferring material from one location to another, problems are sometimes encountered with materials which tend to stick to the conveyor belt. A principal example of this problem is in the transfer of heated asphalt mix of the type used in road building. Typically, the asphalt mix is dumped from a mixing machine to the surface of the conveyor belt at one end, for delivery to a waiting delivery truck at the discharge end of the conveyor. Unfortunately, the hot asphalt mix tends to stick to rubber belt surfaces used for the conveyor belt, and instead of spilling off the end, the material tends to stick to the rubber belt surface and continue on around with the conveyor belt on its return path.
Of course one solution to this problem is to use an articulated steel type conveying track rather than a rubber conveyor belt, but because this solution is rather expensive, it is more common to use a rubber belt and to try to scrape the asphalt off or to simply put up with the problem. The prior art has used many different types of scrapers including stretched wires and blades in an attempt to remove the sticking asphalt from the belt. One problem with the prior art is that the scraping device itself eventually becomes clogged with the asphalt mix sticking to it. Another problem is that there is a metallic splice at some point in the belt which can be damaged when it comes past the scraper. Alternatively, the metallic splice might damage the scraping device.